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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
//
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package org.apache.doris.fs.io;

import java.io.IOException;
import java.io.InputStream;

/**
 * DorisInputStream is an abstract base class for input streams in the Doris filesystem layer.
 * <p>
 * This class extends {@link InputStream} and provides additional methods for position-aware
 * stream reading, such as retrieving the current position and seeking to a specific position.
 * Implementations of this class enable Doris to interact with various storage backends in a unified way.
 */
public abstract class DorisInputStream extends InputStream {

    /**
     * Returns the current position in the input stream.
     * <p>
     * The position indicates the number of bytes read from the beginning of the stream.
     *
     * @return the current byte offset in the stream
     * @throws IOException if an I/O error occurs while retrieving the position
     */
    public abstract long getPosition() throws IOException;

    /**
     * Seeks to the specified position in the input stream.
     * <p>
     * After calling this method, the next read will occur at the given byte offset.
     *
     * @param position the byte offset to seek to
     * @throws IOException if an I/O error occurs or the position is invalid
     */
    public abstract void seek(long position) throws IOException;
}
